The Fiat-Abarth 750 Zagato will be offered by Bonhams during its Greenwich Concours d’Elegance sale which takes place at the beginning of next month but the car’s history is virtually non existent and it also comes without a chassis number as well as the oddity of a larger than standard fuel tank. As such it’s expected to fetch between US$10,000 and US$20,000.

The story of this model goes back to the founding of Carrozzeria Zagato in 1920 by Ugo Zagato, in Milan, and the first bodies would roll out of workshop built out of aluminium on Fiat 501 chassis.

Very soon Zagato added Alfa Romeo as a customer and would simultaneously build bodies on Bianchi, Diatto and Itala chassis. Maintaining a various group of products, aircraft parts were produced for Pomilio, for whom he had worked during the war.

Forced to diversify during the 1930s, Zagato took on the building of truck cabs for Isotta-Fraschini, a job that kept him busy until Allied bombs laid waste to his workshops in 1943. A new plant in 1946, however, put the firm back in business, and Ugo's son, Elio, joined the company.

Zagato had a good amount of experience with Fiat, having built a 750 GT coupe on the Fiat 500 chassis beginning in 1952. A sports spider in 1953 had a tubular frame and power trains from either the Fiat 1100 or 1400.

Commissions from Alfa Romeo and Ferrari followed in short order. From 1955, Zagato took on the production of coupe bodies for Carlo Abarth's new Fiat-based 750.

The Abarth 750 was based on the Fiat 600, its 633cc engine enlarged to 747cc, which nearly doubled the horsepower. With a single two-barrel carburettor and a 4-speed manual transaxle it produced 43bhp at 6,000rpm. The 750 also had four-wheel independent suspension and drum brakes all round.
 
With Allemano building bodies for the spider version of his car, Abarth turned to Zagato for a coupe. The coachbuilder's sketches for the body had a roof so low that there was scant headroom for a person of normal stature, so twin bulges were put into the contour. The result was immediately nicknamed "Double Bubble," after a well-known brand of American chewing gum.

Bonhams describe this car as being from 1957 and say it's "a highly original and complete Fiat-Abarth Zagato sports car." It’s a recent ‘barn discovery’ by Chasing Classic Cars star Wayne Carini, one of a trio of Fiat-Abarths which will all be solid in Greenwich, albeit as individual lots. The discovery of this remarkable triple Abarth collection is featured in a current season episode.

The auctioneers add: “The car is in need of a restoration, but it is quite complete and sound. A notable feature of this car is the enlarged fuel tank, perhaps alluding to some past competition use. The car is accompanied by extra spares and components, so a careful inspection of the car regarding its completeness is recommended." It will be sold off on 3 June.